S3eidat Tools

Make a complete favicon set from a letter/emoji/short text or from an image: favicon.ico (16, 32, 48 px), favicon-16x16.png, favicon-32x32.png, apple-touch-icon.png (180, square, solid), android-chrome-192x192.png and -512x512.png, site.webmanifest and head-snippet.html with the <link> tags. Rounded square with background colour (or transparent), corner radius and padding in %. Writes everything into one folder. Web version: https://s3eidat.github.io/favicon-forge/

Decode Base64 back into a file: accepts a data URI, a CSS url("data:…") rule, an <img src="data:…"> tag, URL-encoded SVG data URIs, or raw Base64 (standard or URL-safe, line breaks allowed). Detects the real type from the bytes, warns when it differs from the declared one, and writes decoded.<ext>. Give the text inline or as a path to a text file. Web version: https://s3eidat.github.io/image-to-base64/

Extract the main colours of an image with their share of the picture: k-means (default, deterministic) or median cut, 1-16 colours, sorted by share. Transparent pixels are ignored. Returns hex + rgb + % per colour, CSS custom properties (:root { --color-1 … }) or JSON, and optionally writes the website's swatch strip as palette.png. Same algorithm and sampling as the website, so the colours match. Web version: https://s3eidat.github.io/palette-from-image/

Make a placeholder image of any size (up to 8000 px a side): solid background with centred text (default "W × H", "\n" for line breaks), auto-fitted font size or a fixed one, PNG / JPEG / WebP / SVG. Size presets for web, social media, IAB ads and devices. Optionally returns a data URI / <img> tag for inlining. Text uses Inter when installed, else a system sans-serif. Web version: https://s3eidat.github.io/placeholder-image/

Resize an image by pixels or percent, keeping the aspect ratio. Give width or height (the other side follows), or both: fit "cover" (default, as on the website) centre-crops to that ratio first so nothing is stretched, "contain" fits inside the box, "fill" stretches. Optional crop ratio (1:1, 4:5, 3:2, 16:9, 9:16, orig) or crop box before resizing, social-media presets, output JPEG/PNG/WebP/AVIF. Up to 16384 px a side. Output name: <name>-<W>x<H>.<ext>. Web version: https://s3eidat.github.io/image-resize/

Rotate an image clockwise by 90, 180, 270 or any angle (the canvas grows to fit; new corners get `background`), and/or flip it horizontally (mirror) or vertically. Flips apply after the rotation, as seen on screen. EXIF orientation is applied first (autoOrient, default on), so with angle 0 this simply "fixes" sideways phone photos. Output JPEG/PNG/WebP/AVIF ("keep" = same as input), name <name>-rotated.<ext>. Web version: https://s3eidat.github.io/photo-filters/

Rasterise an SVG to a crisp PNG: scale (1×, 2×, 3×, 4×… default 2×), a target width or height (aspect kept), or an exact size (stretched). Units (px, pt, mm, cm, in) and viewBox-only SVGs are understood; transparent background or a solid colour. Scripts, event handlers and external references are removed first. Name <name>@2x.png. Web version: https://s3eidat.github.io/svg-to-png/

Encode an image (or any file) as Base64: a data URI, bare Base64, a CSS background-image rule, an HTML <img> tag (with width/height), Markdown, or for SVG a URL-encoded data URI (usually ~30% smaller). Detects the type from the bytes and warns when the result is too big to inline (over 10 KB: slows pages; over 1 MB: use a normal file). Results longer than maxChars are written to a .txt file instead of being returned. Web version: https://s3eidat.github.io/image-to-base64/

Add a text or logo watermark to a photo. Size is a % of the photo width, margin a % of the shorter side, so the result looks the same on any resolution. One of 9 positions or tiled across the whole image (brick pattern), with opacity, rotation, colour, weight and a soft shadow for text. Logo: any image (PNG with transparency works best). Output keeps the input format (JPEG/PNG/WebP) or as chosen; name <name>-watermarked.<ext>. Text uses the Inter font when installed, else a system sans-serif. Web version: https://s3eidat.github.io/watermark/

Check whether an IPv4 or IPv6 address falls inside a range given as CIDR ("10.0.0.0/8", "2001:db8::/32"), a dash range ("192.168.1.10 - 192.168.1.60") or a single address. Web version: https://s3eidat.github.io/subnet-calc/

Validate, pretty-print (2 or 4 spaces, tab) or minify JSON, optionally sorting object keys (deeply). Invalid JSON gives a clear error with line and column and the lines around it. Also returns size, key count, depth and value count. Give "text" or a file "path"; "output" writes the result to a file. Uses the standard JSON parser (no comments or trailing commas). Web version: https://s3eidat.github.io/json-studio/

Pick values out of JSON with a JSONPath expression. Supported: $ (root, optional), .key, ['key'], [0], [-1], [*], .*, ..key (recursive), [start:end:step] slices, unions [0,2] / ['a','b'], and filters like [?(@.price < 10 && @.tags)] (==, !=, <, <=, >, >=, =~ /regex/i, &&, ||, !, .length). Returns each match with its path (the same path style the website's tree view copies, e.g. $.store.book[0].title). Give "text" or a file "path". Web version: https://s3eidat.github.io/json-studio/

Convert JSON to CSV. An array of objects becomes one row per object with nested objects/arrays flattened to dotted columns (address.city, tags.0); an array of arrays is written as-is. Fields are quoted only when needed (delimiter, quotes, line breaks, leading/trailing spaces); CRLF line ends. A formula guard (on by default) prefixes cells starting with = + - @ so spreadsheets don't run them. Give "text" or a file "path". Web version: https://s3eidat.github.io/csv-json/

Generate type definitions from a JSON sample: TypeScript interfaces (or type aliases), Go structs with json tags (initialisms like ID/URL, pointers for optional/nullable, optional omitempty), Python dataclasses (snake_case fields with the original key noted) and Zod schemas. All items of an array are merged into one type (missing keys become optional, null makes a field nullable, int+float → number/float64, mixed values → unions); identical shapes share one name. These four are every language the website supports. Give "text" or a file "path". Web version: https://s3eidat.github.io/json-to-types/

Convert JSON to YAML (js-yaml dump: no line wrapping, no anchors; strings that would read as numbers/booleans are quoted). Options: 2 or 4 space indent, sort keys, and write a top-level array as a multi-document YAML stream (--- per item). Invalid JSON gives line and column. Give "text" or a file "path". Web version: https://s3eidat.github.io/yaml-json/

Decode a JSON Web Token (a leading "Bearer " is fine): header, payload, iat/nbf/exp/auth_time as ISO dates with relative time, expired / not-yet-valid status, and named standard claims. If "secret" is given, verifies HS256/HS384/HS512 signatures (secret as text or Base64URL). RS/ES/PS tokens are decoded but not verified (needs a public key). Encrypted JWE tokens can't be read. Web version: https://s3eidat.github.io/jwt-inspector/

Make a GitHub-flavoured Markdown table from CSV, TSV, a JSON array (of objects or of arrays), an existing Markdown table (to re-align / re-pad it) or a "rows" array. Per-column alignment (left, center, right), columns padded to line up (optional), pipes escaped as \| and line breaks as <br>. CSV delimiter (comma, semicolon, tab) is detected from the first line. Give "text", a file "path" or "rows". Web version: https://s3eidat.github.io/markdown-table/

Read a Markdown table (pipes optional at the ends, \| escapes, <br> as line breaks) back into data: JSON objects keyed by the header, JSON arrays, or CSV; also returns each column's alignment. Uses the website's Markdown import. Give "text" or a file "path". Web version: https://s3eidat.github.io/markdown-table/

Generate the <head> HTML for SEO and social sharing: <title>, meta description, canonical link, Open Graph (og:type, url, title, description, image + alt, site_name, locale) and X/Twitter card tags. All values are HTML-escaped. Also checks lengths (title 30–60, description 70–160 characters), URLs and the @handle, and shows how Google, Facebook and X would truncate the title and description. URLs without a scheme get https://. Optionally writes the tags to an .html file. Web version: https://s3eidat.github.io/meta-tags/

Estimate how strong a password really is, the way attackers guess (zxcvbn-style): finds common passwords (1,282-entry list), dictionary words (also reversed, capitalised or l33t), keyboard walks, sequences, repeats, years and dates, then the cheapest way to guess the whole thing. Returns a 0–4 score, entropy bits, guesses, crack time for 4 attack scenarios, the pieces found, and advice. Offline only: no breach lookups, nothing stored or logged. Web version: https://s3eidat.github.io/password-check/

Generate strong random passwords (8–128 chars; lower/upper/digits/symbols; skip look-alikes Il1|O0o; exclude your own characters; require every chosen set) or passphrases (3–12 words from the website's 2,381-word list, separator, capitalise, add a number). Returns 1–1000 results with exact entropy bits, a strength grade and the time to crack at 100 billion guesses/s. Always crypto random (OS CSPRNG, rejection sampling); nothing is stored or logged. Web version: https://s3eidat.github.io/pass-forge/

Shrink a PDF by re-rendering every page as a JPEG image (best for scans and photo-heavy files). Presets like the website: email (96 DPI, quality 55), balanced (144 DPI, 72), high (220 DPI, 85); or set dpi/quality yourself; optional grayscale. The result loses selectable text, links and form fields. Reports before/after size and a verdict ("bigger" means keep the original: the PDF was already efficient). Web version: https://s3eidat.github.io/pdf-compress/

Make one new PDF from selected pages of a PDF, e.g. "1-3, 7, 10-" (order as written, each page once). The rest of the file is left out. To reorder, duplicate or delete pages use pdf_organize. Web version: https://s3eidat.github.io/pdf-split/

List the fillable fields of a PDF form in reading order: name, readable label, type (text, checkbox, radio, dropdown, list, signature, button), page, current value, options, and whether it is required / read-only / multi-line. Use the names with pdf_form_fill. Web version: https://s3eidat.github.io/pdf-fill/

Fill PDF form fields by name (get names from pdf_form_fields): text as strings, checkboxes as true/false, radio groups and dropdowns by option text, lists as arrays. Optionally flatten (bake the answers into the page, no longer editable). Only changed fields are redrawn. Text the standard font cannot draw (Arabic…) is kept and viewers are asked to draw it, but cannot be flattened. Web version: https://s3eidat.github.io/pdf-fill/

Make a PDF from images (JPEG, PNG, WebP, GIF, TIFF, AVIF, SVG…), one image per page, in the order given. Page size A4, Letter, or "fit" (page = image size at 96 dpi); orientation auto/portrait/landscape; margin in mm; quality "original" (JPEG/PNG kept as-is), high (≤3000 px, JPEG 90), medium (≤2000 px, 75) or small (≤1400 px, 60). Photos are turned upright from their EXIF orientation. Web version: https://s3eidat.github.io/images-to-pdf/

Quick facts about a PDF for planning the next step: page count, page sizes (points, mm, paper name such as "A4 portrait", grouped by size), rotated pages, encryption, PDF version, form field count, title/author, and which pages have no text layer (scans that would need OCR). Related web tool: https://s3eidat.github.io/pdf-metadata/

Combine several PDFs into one, in the order given. Each entry can be a file (path or base64) or {file, pages} to take only some pages ("1-3, 5, 8-"; "3-1" keeps reverse order; a page can repeat). Password-protected PDFs must be unlocked first. Web version: https://s3eidat.github.io/pdf-merge/

Show what a PDF reveals about itself: Title, Author, Subject, Keywords, Creator, Producer, creation/modification dates (with time zone), custom info fields, XMP metadata (size, edit history, creator) and the document ID. Optionally returns the XMP XML. Web version: https://s3eidat.github.io/pdf-metadata/

Change PDF info fields (title, author, subject, keywords, creator, producer, dates, custom fields) or strip all metadata: info fields, XMP, page-level data and the document ID, and drop unreachable leftovers from earlier edits so no trace stays in the bytes. Untouched values keep their exact original form. Web version: https://s3eidat.github.io/pdf-metadata/

Rebuild a PDF from a page list: reorder, delete (leave pages out), duplicate (list a page twice) and insert blank pages. "3, 1-2, blank, 5-" puts page 3 first, then 1-2, a blank page (same size as the page before it), then 5 to the end; page 4 is dropped. Optionally rotate pages of the result. Existing page rotation is kept. Web version: https://s3eidat.github.io/pdf-organizer/

Add page numbers to a PDF, plus an optional header and footer line. Format tokens: {n}, {total}, {date}, {filename} (e.g. "Page {n} of {total}", "{n} / {total}", "- {n} -"). Choose the corner/edge, start number, how many leading pages to skip (e.g. a cover), a page range, font, size, colour and margin. Numbers stay upright on rotated pages. Web version: https://s3eidat.github.io/pdf-page-numbers/

Rotate selected pages of a PDF by 90, 180 or 270 degrees clockwise (-90 = counter-clockwise), on top of any rotation they already have. Other pages, links and form fields are left as they are. Web version: https://s3eidat.github.io/pdf-organizer/

Place a signature (or initials, stamp, logo) image on PDF pages at x/y/width in points, measured from the top-left of the page as it is shown (rotated pages are handled). A light paper background is removed by default so scanned signatures sit cleanly on the page. Optional text marks (name, date…) can be added too. This is a visual signature, not a cryptographic digital signature. To draw a signature by hand, use the web version: https://s3eidat.github.io/pdf-sign/

Split one PDF into several PDFs written to a folder: by page ranges (one file per range, e.g. "1-3, 4-6, 7-"), every N pages, or one file per page. Files are named like the website: <name>-pages-1-3.pdf, <name>-part-01.pdf, <name>-page-001.pdf. Use pdf_extract_pages to get a single PDF with chosen pages. Web version: https://s3eidat.github.io/pdf-split/

Render PDF pages to PNG, JPEG or WebP images in a folder (one file per page, named <name>-p001.png…). Choose the DPI (72 = screen size, 150 = default, 300 = print), JPEG/WebP quality, a page range, and a transparent background for PNG/WebP. Very large pages are capped at 16384 px a side / 16.7 megapixels, like the website. Web version: https://s3eidat.github.io/pdf-to-images/

Extract the text of a PDF with lines and paragraphs rebuilt (right-to-left Arabic/Hebrew lines in reading order), as plain text or Markdown, with optional page separators and reflow (join lines, mend hyphenated words). Returns per-page word counts and flags pages with no text layer (scans: this tool does no OCR). Supports page ranges and passwords. Give "output" to write a .txt/.md file instead of returning the text inline. Web version: https://s3eidat.github.io/pdf-to-text/

Stamp a text or image watermark on PDF pages: centred or tiled across the page, with opacity, angle, size, colour and a page range. It reads upright on rotated pages. Text the standard PDF fonts cannot draw (Arabic, CJK…) is stamped as an image. Defaults match the website: "CONFIDENTIAL", Helvetica Bold 72 pt, #d64545, 25% opacity, 45°. Web version: https://s3eidat.github.io/pdf-watermark/

Islamic prayer times (Fajr, Sunrise, Dhuhr, Asr, Maghrib, Isha) for any coordinates + IANA time zone, or a known city, for one day, several days or a whole month, plus the Hijri (Umm al-Qura) date and the next prayer with a countdown. Same astronomy as the website (adhan.js): 13 methods (Jordan Awqaf, MWL, Umm al-Qura, Egyptian, ISNA, Karachi, Dubai, Kuwait, Qatar, Turkey, Singapore, Tehran, Moonsighting), Shafi'i or Hanafi Asr, and the recommended high-latitude rule beyond 48° (overridable). Times are local HH:MM (24 h) in the given zone, plus UTC ISO. Coordinates are rounded to 4 decimals like the site. Web version: https://s3eidat.github.io/prayer-times/

Qibla direction (great-circle bearing from true north to the Kaaba in Makkah) and distance from any coordinates or a known city, with the compass point, a "face north, then turn right/left N°" instruction, and (if you give a device heading) how far to turn. Bearings are from TRUE north; a magnetic compass can differ by a few degrees. Web version: https://s3eidat.github.io/qibla-finder/

Make a QR code as SVG or PNG for a link, plain text, Wi-Fi login, contact card (vCard 3.0), email, SMS, phone call or map location. Same encoder as the website (qrcode.js: versions 1-40, error correction L/M/Q/H, smallest version that fits, best mask), UTF-8 so Arabic/emoji work. Options: size in px, quiet-zone margin, colours, square/rounded/dots modules, and an optional centre logo (forces level H). Returns the file path, the exact encoded text, version, module count and contrast warnings. Max about 2.9 KB of data at level L. Web version: https://s3eidat.github.io/qr-studio/

Read (decode) a QR code from an image file: photo, screenshot or scan (PNG, JPEG, WebP, GIF, TIFF, AVIF, SVG). Uses jsQR like the website, trying several sizes and inverted (light-on-dark) codes. Returns the text plus what it is (Link, Wi-Fi, Contact, Email, SMS, Phone, Location, Event or Text) with parsed fields, and safety notes for links (http, hidden @ user part, punycode lookalikes, bare IPs, odd ports). Links are never opened. Reads one code per image. Web version (with camera): https://s3eidat.github.io/qr-scanner/